Shaking mechanism



Dec. 29, 1936. H. c. DEMPSEY ET AL SHAKING MECHANI SM Filed sept. 7, 1934 Patented Dec. 29, 1936 UNi'rsD STATES PATENT OFFICE SHAKING MECHANISM Application September 7, 1934, Serial No. 743,074

1 Cla-im.

This invention relates generally to shaking mechanisms adapted to convert rotary motion into the reciprocating shake movement required for screens of separators and the like, and more specifically to shaking mechanisms of the type which includes a plurality of drums that are rotated rapidly in opposite directions and are provided with weights or weighted portions adapted through the action of centrifugal force to impart to the shaking mechanism and to a sepalo rator screen, or other element to which the shaking mechanism is attached, reciprocatory movement, the predominant object of the invention being to provide a shaking mechanism of the l, type referred to having rotating drums, the

weights or weighted portions of which are adjustable relative to the centers of the drums so 'that the extent of reciprocal travel of the shaking mechanism and the speed thereof may be regulated. In the efficient operation of separators it is necessary that screens or sieves be provided having perforations or openings of different sizes for use in cleaning different products. Also, the extent of the travel and the speed of movement of the screens or sieves bear a fixed relationship to the sizes of the perforations or openings of the screens or sieves, the travel of the screens or sieves being shorter and the speed of movement thereof being greater when the openings are smaller, and the travel of the screens or sieves being longer and the speed of movement of s-aid screens or sieves being slower when the perforations or openings of the screens or sieves are larger. Fast speed of movement and short travel of the screens or sieves require less centrifugal force, while slower speed of movement of the screens or sieves and longer travel thereof require greater centrifugal force. As already stated herein, the improved shaking mechanism disclosed herein includes rotary drums having weights which are capable of being adjusted toward and from the centers of the drums, hence any desired centrifugal force within certain limits may be obtained by adjusting the weights of the drums to the proper positions with respect to the centers of the drums.

All of the shaking mechanisms with which we are familiar other than the improved mechanism disclosed herein are provided with rot-ary drums having weights or weighted portions that are immovably xed with respect to the centers of the drums, and therefore these other shaking mechanisms are capable of producing reciprocal 55 movement of one distance and speed, and if a diiferent speed of movement or different extent of travel of the screens or sieves were desired, a differently arranged shaking mechanism had to be used. In the use of our improved shaking mechanism, however, the extent of reciprocal` travel of the screens or sieves of separators and the 'speed of such travel may be regulated by simple manipulations which result in the weights of the drums being shifted toward or away from the centers of the drums. 10

Fig. l illustrates a side elevation of the improved shaking mechanism showing same applied to a screen or sieve or other element.

Fig. 2 is a section on line 2-2 of Fig. l.

In the drawing, wherein is shown for the pur- 15 pose of illustration, merely, one embodiment of the invention, A designates the shaking mechanism generally. The shaking mechanism A includes a frame which includes a base I from which a pair of parallel, spaced apart arms 2 20 extend in an outward direction. The arms 2 may be separate elements secured to the base I of the frame, or, if preferred, said arms 2 may be formed integrally with said base I. At their outer ends the arms are provided with bearings 3 25 which receive a shaft 4, said shaft being nonrotatably secured to said bearings by set screws 5.

Mounted for rotary movement about the shaft 4 at a point adjacent to one of the arms 2 is a mitre gear 6 provided with an elo-ngated hub 30 portion 6', said mitre gear having associated therewith a suitable bushing 'l for contact with the shaft 4. Mounted for rotary movement about the shaft at a point adjacent to the opposite arm 2 is a similar mitre gear 8, this latter mitre 35 gear being provided with an elongated hub portion 8 and having a suitable bushing 9 associated therewith for Contact With the shaft 4.

Fixed to the shaft 4 at the approximate center thereof by means of a set screw Illa is a spider IIJ, 40 which includes a hub portion I0 and a pair of spindles Il which extend outwardly from said hub portion, as shown most clearly in Fig. 2. Mounted for rotation on the spindles II of the spider lil is a pair of mitre gears I2 and I3, the 45 teeth of the mitre gears I2 and I3 being arranged in mesh with the teeth of the mitre gears 6 and 8. The mitre gears I2 and I3.have associated therewith suitable bushings I4, and elements I5 secured to the spindles II by screws I6 maintain 50 the mitre gears I2 and I3 in position on the spindles.

Secured to the elongated hub portion of the mitre gear 6 by means of the set screw I1 is a drum I8, and secured to the elongated hub portion of the mitre gear 8 by means of a set screw I9 is a similar drum 20. Each drum includes a hub portion 2| which surrounds the elongated hub portion of the associated mitre gear, a side wall portion 22, and a circumferential flange portion 23, the side wall portions of the drum being located at the opposite outer sides of the assem- Vbled drums, and the circumferential flange portions being extended inwardly toward each other in alined relation and with the inner edges thereof spaced from each other a slight distance.

Mounted within each of the drums I8 and 20 is a Weight 24 Which has the side elevational shape shown by dotted lines in Fig. 1 and the cross-sectional shape shown in Fig. 2. The weights 24 are movably attached to the side wall portion of the drums by cap screws 25, which pass through slots 26 formed through'the side Y Y wall portions of the drums and extended into screw-threaded openings 2 formed in the weights. At theapproxiniate center of Yeach of the weights-as viewed in Fig. 1 said weight has formed therethrough a screw-threaded opening 28 through which a screw-threaded adjusting screw 29 passes. At its outer end each adjusting screw 29 passes through a smooth opening 30 formed in the thickened portion 3l of the circumferential flange portion of the associated drum, and at its inner end said adjusting screw is rotatably attached to an ear 32 which is extended inwardly from the inner face of the side wall portion Yof the drum. The rotatable connection between the inner end of each adjusting screw andthe associated ear 32 is accomplished by providing the adjusting screw with a reduced portion 33 adjacent to its inner end which passes through an opening formed through the ear, and arranging at the extreme inner end of the adjusting screw a head portion 34 which is of greater diameter than the reduced portion 33. Shoulders provided by the head portion 34 and at the point lwhere the Vreduced portion 33 of the adjusting screw Vjoins the set screw proper contact with opposite faces of the ear 32. whereby rotary movement of said adjusting screw with respect to the ear is permitted, while longitudinal movement of the adjusting screw is prevented.

At the vopposite ends of the shaft 4 cups 35 for a lubricant are provided, said shaft being provided with passageways. (not shown) `which conduct lubricant from the cups 35 to the working faces of the shaft and mitre gears 6 and 8.

In the use of the shaking mechanism disclosed herein rotary motion is applied to one of the drums by means of a power transmission belt (not f shown) or byany other suitable means, and because of the arrangement of the mitre gearing 6-8-l2-I3 the other drum' is rotated in the opposite direction. Thus, when the drums are in motion the weights 24 pass each other twice in each complete cycle of the drums, and also twice in each cycle of the drums the weights are diametrically opposite to each other, whereby they balance each other. When the weights are passing each other the centrifugal force exerted is in proportion to their weight and the 'distance they are positioned from the centers of the drums, and after they pass each other the centrifugal force is neutralized by the balancing action of the weights. The weights then pass each other again at a point opposite to the point at which they rst passed. Thus the weighted drums, rotating in opposite directions, produce in each cycle of the drums two centrifugal impulses and two neutralizing impulses. This imparts a reciprocating motion to any element to which the shaking mechanism is attached.

The extent of the centrifugal action obtained during rotation of the drums inl opposite directions may be decreased or increased by adjusting the weights 24 toward or away from the centers of the drums, hence the degree of Vreciprocal travel of the shaking mechanism and the speed of such travel may be likewiserregulated by adjustment of the weights. When in the use of the improved shaking mechanism it is desired to alter the extent of reciprocal travel of the mechanism and the speed of such travel, it is necessary merely to unscrew the cap screws 25 slightly and rotate the adjusting screws 29 in one or the opposite direction.. Such rotation of 4the adjusting screws causes the weights to move longitudinally of the adjusting screws, due to the rotation of the adjusting screws within the screw-threaded openings of the weights, and in thisv manner the weights may be moved toward or from the cen#- ters of the drums. When the weights have been positioned with respect to the centers of the drums so as to give the desired centrifugal force,

the cap screws are tightened to hold the weights in the positions to which they have been adjusted and the shaking mechanism is ready for use.

We claim:

A shaking mechanism including a pair of drums geared for rotation in opposite directions, one of said drums constituting means to which rotary motion is directly imparted by power means whereby the shaking mechanism is operated,

weights supported by said drums, adjusting f screws for adjusting'said weights toward and said screw-threaded locking elements 

